The invention refers to an apparatus for finishing products coming out from a machine for folding and gluing cardboard or paperboard products with a back.
With cardboard or paperboard products with a back, the simple folders are meant, provided with document-carrying pockets, for discs, CD, DVD etc.
Machines are known which perform the folding of the preformed cardboard or paperboard (punched) sheets, the application on the suitably made glue strips and the gluing of the suitable parts for obtaining the finished product. Often these machines make products with defects which can be of low but also of unacceptable entity. These defects consist in that the backs which should be kept in a vertical position by the glue actually at the end of the production are not properly vertical but inclined to the vertical.
This is due to the fact that the glue has not completely hardened before the product coming out of the machine, and therefore the folded parts have the time to be slightly released before the glue takes hold completely.
On the other hand, the glue must not take hold too rapidly because otherwise it would harden before the bonding operations come to the end, which would cause still greater damages.
In certain cases the inclination with respect to the vertical of the backs is acceptable as it is scarcely visible to the naked eye; in other cases, say in most cases, this inclination is clearly visible and also is visible the open space which is seen through the corners between back and back which are not perfectly aligned along the vertical. Attempts were made to overcome such production defects, normally by changing the characteristics of taking hold of the used glue, but the results have been found to be unsatisfactory.